Minnesota Vikings: 15 best free agent acquisitions of all-time

While on the topic of making a huge impact in a short time, it may not get more intense than Pro Football Hall of Fame quarterback Brett Favre. Once a division rival with the Green Bay Packers, it was shocking to see him wearing a purple and gold jersey and playing against his former squad.

Favre was a legend in Green Bay. He led the Packers to a win in Super Bowl XXXI, went to the Pro Bowl nine times, was named All-Pro First Team three times and earned the AP NFL Most Valuable Player award winner three times.

After spending one season with the New York Jets after his exit from Green Bay, Favre joined the Vikings for two seasons. He immediately made the team a Super Bowl contender. Like with Randall Cunningham, the Vikings’ prized quarterback acquisition got them within one game of the Super Bowl, coming up short against the New Orleans Saints.

Favre couldn’t recreate the magic from his 2009 season in his second year with Minnesota, as he he threw for 4,202 yards and 33 touchdowns with only seven interceptions in his first year with the Vikings. The quarterback didn’t return to football after the 2010 season when he suffered a concussion against the Chicago Bears at TCF Bank Stadium.